JP3145159B2 - Roll nip pressure measurement method, test specimen for the measurement, and nip roll using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring a roll nip pressure of a fixing roller or the like in an electrophotographic copying machine or the like, a test specimen for the measurement, and a nip roll using the same.

[0002]

2. Description of the Related Art A nip roller in a papermaking machine and a fixing roller in an electrophotographic copying machine are provided after a wet paper or pressure-sensitive paper having a predetermined area supplied is sandwiched between two rotating rolls and a predetermined pressure is applied. , And send it out to the next transport path.
At this time, whether or not the transport paper is uniformly pressed with an appropriate nip pressure in the axial direction of the roll (the direction orthogonal to the transport direction of the paper), in other words, over substantially the entire width of the transport paper. Has a significant effect on papermaking and copying quality, so adjusting the interval between the two rolls during shipping or maintenance, that is, adjusting the nip pressure, is important for maintaining high papermaking and copying quality. Has significant significance. Therefore, various roll nip pressure measuring methods have been conventionally proposed.

FIG. 2 is a configuration diagram showing a roll nip pressure measuring device in a papermaking machine to which the conventional method is applied (for example, see Japanese Utility Model Laid-Open No. 59-65000). In FIG. 2, 1 is a nip roll, 2 is a crown control roll, 3
Is a nip pressure adjusting device, 4 is a plurality of strain gauges arranged in a line in the axial direction of the roll on the inner surface of the iron core 1a of the nip roll 1 and the rubber cover 1b, 5 is a lead wire, 6 is a measuring instrument, Reference numeral 7 denotes an amplifier, 8 denotes a nip pressure distribution display device, and 9 denotes a pressing force correction device.

In this apparatus, when the conveyed wet paper is supplied between the nip roll 1 and the control roll 2, the nip pressure at this time is detected by each strain gauge 4 and measured by a measuring device 6. Is done. The output signal of the measuring device 6 indicating the measurement result is input to the nip pressure distribution display device 8 via the amplifier 7. Thereby, the pressure distribution in the roll axis direction (the width direction of the wet paper) is displayed on the nip pressure distribution display device 8.

If the measured nip pressure in the width direction of the wet paper is not uniform, it is immediately displayed on the nip pressure distribution display device 8 as an uneven pressure distribution. At this time, the pressing force correction device 9 calculates a correction signal based on the output signal of the display device 8 and sends the correction signal to the nip pressure adjusting device 3 so as to have an optimum nip pressure distribution. Thereby, the interval between the nip roll 1 and the control roll 2 is adjusted, and the pressure is controlled so as to have a uniform pressure distribution.

As a method of measuring the nip pressure of a fixing roller in an electrophotographic copying machine, conventionally, pressure-sensitive paper is supplied to a fixing roller, and the pressure-sensitive state of the pressure-sensitive paper sent from the roller is visually inspected. A method of adjusting the interval between the two rolls based on this is adopted.

[0007]

As described above, in the apparatus to which the conventional method is applied, the strain gauge 4 for sensing the nip pressure is used.
Are arranged in the axial direction of the nip roll 1, so that the roll nip pressure on a so-called line from one side to the other side in the axial direction of the roll can be measured simultaneously.

However, since the strain gauge 4 is not arranged over the entire circumference of the nip roll 1, ie, not two-dimensionally, the roll nip pressure cannot be measured continuously in the wet paper web transport direction. Further, since the nip roll 1 has an elastic surface, the nip pressure is distributed also in the paper transport direction (the direction perpendicular to the roll axis direction), but the distribution of the nip pressure cannot be measured. Therefore, it is not possible to obtain a linear pressure distribution on the entire peripheral surface of the rotating roll, and it is difficult to adjust the nip pressure with high accuracy, and there is a disadvantage that the papermaking quality cannot be sufficiently improved.

In the method using pressure-sensitive paper, only the maximum load portion is recorded, and a uniform pressure distribution cannot be obtained as a whole. In addition, since the judgment must rely on human vision, the inspection results vary depending on the skill of the judge, and it is difficult to adjust the nip pressure with high accuracy, and it is not possible to sufficiently improve the fixing quality. There is. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a real-time linear pressure distribution on the entire circumferential surface of a roll, and a method for measuring a roll nip pressure that enables highly accurate nip pressure adjustment. And a test body for measuring the same and a nip roll using the same.

[0010]

According to a first aspect of the present invention, there is provided a method for measuring a roll nip pressure between two rolls which sandwiches and feeds a supplied planar body in a predetermined direction. Strip- shaped pressure-sensitive elements that output an electrical signal corresponding to the pressure so that their intersections overlap each other
A predetermined number of each in the axial and circumferential direction of the roll
A sheet specimen distributed at a distance is supplied between two rolls, and a roll nip pressure in the axial direction of the roll is measured based on the output electric signal, and the measurement is performed over the entire circumference of the roll. It was performed continuously.

According to a second aspect of the present invention, in a roll nip pressure measuring test body which is supplied between two rolls and detects a roll nip pressure, a belt-shaped pressure-sensitive element which outputs an electric signal corresponding to a pressing force intersects with each other. So that they overlap
A predetermined number of each in the axial and circumferential direction of the roll
A plurality of band-shaped electrodes for detecting the electric signal are distributed at predetermined intervals in the axial direction and the circumferential direction of the roll so that the intersections overlap each other, and the pressure-sensitive electrodes are arranged at intervals. The length of the element distribution region in the supply direction between the rolls was set to be equal to or longer than the entire circumference of the rolls.

According to a third aspect of the present invention, there is provided a nip roll for sandwiching and feeding a supplied planar body in a predetermined direction.
A band-shaped pressure-sensitive element that outputs an electrical signal corresponding to the pressing force
Make sure that the cross section of the rolls overlaps
And distribute them at predetermined intervals in the circumferential direction.
Rutotomoni, the electrical signals respectively are distributed at predetermined intervals by a plurality in the axial direction and the circumferential direction of the roll so that together intersection of band-shaped electrodes for detecting overlap the previous
The electrodes and the pressure-sensitive elements were arranged over the entire circumference of the roll with respect to the inside of the roll surface.

[0013]

According to the present invention, when a test body having pressure-sensitive elements distributed in a plane is supplied between two rolls, a nip pressure is applied to the pressure-sensitive elements, and the nip pressure is applied to each of the pressure-sensitive elements according to the pressure. The output electric signal is output. Thereby, the roll nip pressure in the entire area or at least two areas in the axial direction of the roll is measured simultaneously in the axial direction of the roll. The pressure distribution in the circumferential direction of the roll is also measured. This measurement is continuously performed over the entire circumference of the roll as the roll rotates, and a continuous nip pressure distribution over the entire roll is obtained.

According to the second aspect, when the test object is supplied between the two rolls, the nip pressure is applied to the pressure-sensitive elements, and each pressure-sensitive element outputs an electric signal corresponding to the pressure. This electric signal is detected by the electrode and sent to the measurement control system. In this way, the roll nip pressure in the entire area or at least two areas in the axial direction of the roll is measured simultaneously in the axial direction of the roll. The pressure distribution in the circumferential direction of the roll is also measured. This measurement is continuously performed over the entire circumference of the roll as the roll rotates, and a continuous nip pressure distribution over the entire roll is obtained.

According to a third aspect of the present invention, when the sheet is supplied between the two rolls, a nip pressure is applied to the pressure-sensitive elements arranged over the entire circumference of one of the rolls. Outputs an electric signal corresponding to the pressure. In this way, the roll nip pressure in the entire area or at least two areas in the axial direction of the roll is measured simultaneously in the axial direction of the roll. Also,
This measurement is continuously performed over the entire circumference of the roll as the roll rotates, and a continuous nip pressure distribution over the entire roll is obtained.

[0016]

FIG. 1 is an external perspective view for explaining one embodiment of a roll nip pressure measuring method according to the present invention, and FIG.
FIG. 2 is a sectional view taken along line AA in FIG. In the figure, reference numeral 10 denotes a planar test specimen (hereinafter referred to as a test specimen), and reference numeral 20 denotes a fixing roller in an electrophotographic copying machine.

The test body 10 is, for example, 500 mm long × 29 wide.
A sensor body 11 of 0 mm × thickness 112 μm and a cover 1 made of, for example, a 20 μm thick insulating rubber covering this surface.
2 and a connection cable 14 pulled out of the sensor main body 11. A connector 15 is provided at the end of the connection cable 14, and a control system (not shown) of a higher-level device including a computer including a display device is provided.
It can be easily connected to.

The sensor main body 11 has a structure in which a first base portion 11X and a second base portion 11Y are overlapped with each other in an arrangement relationship described later.

The first base portion 11X is, for example, 500 mm long.
A base 111X made of polyimide resin having a width of 290 mm and a thickness of 20 μm, and a copper foil having a length of 280 mm × a width of 0.5 mm × a thickness of 16 μm on one surface of the base 111X in the X direction of the coordinate system set in the drawing. A plurality of strip-shaped electrodes 112X formed in parallel (32 rows repetition) at intervals (for example, 0.5 mm), and 280 mm long × 0.5 mm wide × 20 μm thick formed on each electrode 112X For example, a plurality of strip-shaped pressure-sensitive sensors 113 made of pressure-sensitive conductive ink
X.

Similarly, the second base portion 11Y has a length of 500
The base 111Y is made of a polyimide resin of mm × 290 mm × 20 μm in thickness, and a copper foil of 490 mm × 0.5 mm × 16 μm in thickness in the Y direction of the coordinate system set in the drawing on one side of the base 111Y. Predetermined interval (for example, 0.5mm)
A plurality of strip-shaped electrodes 112 formed in parallel
Y and a plurality of strip-shaped pressure-sensitive sensors 113Y formed of, for example, pressure-sensitive conductive ink and having a length of 490 mm, a width of 0.5 mm, and a thickness of 20 μm formed on each electrode 112Y. However, in the second base portion 11Y, as shown in FIG. 4, three regions (for example, each having a width of 64 mm) L, which correspond to both sides in the axial direction of the fixing roller 20 and the center thereof.
An electrode 112Y and a pressure-sensitive sensor 113Y are formed on C and R.

The sensor body 11 includes the first base 1
The 1X and the second base portion 11Y are configured to be overlapped so that the electrode forming surfaces face each other, and the pressure-sensitive sensors 113X and 113Y are orthogonal to each other and contact at the intersection. The electrode 112Y is directly connected to the connection cable 14 at the end as the Y side. Electrode 11
The 2X is connected to the lead 114X through the through hole 115X of the base 111X as shown in FIG. 5, and is connected to the X side of the connection cable 14. FIG. 5 shows the relationship between the electrode 112X, the lead 114X, and the through hole 115X. The same lead 114X and the same through hole 115X are connected once for every 64 electrodes 112X.

Further, each of the electrodes 112X and 112Y is connected to a connection cable 14 drawn from the rear end of the sensor body 11 by printed wiring to the bases 111X and Y at each intersection. 1
A change in resistance of the pressure-sensitive sensors 113X and 113Y between 12Y is detected by a control device 30 described later as a change in current flowing between the electrode 112X and the electrode 112Y.

The fixing roller 20 includes, for example, a heating roll 21 having a built-in heating heater and having a diameter of 50 mm and a length of 300 mm.
It is composed of a pressure roll 22 having a diameter of, for example, 40 mm and a length of 300 mm, on the surface of which a rubber layer such as silicone rubber is formed. The test body 10 is sandwiched, pressurized (and heated), and sent out in a predetermined direction.

As can be seen from the diameter of the fixing roller 20, in the case of this embodiment, the length of the test piece 10 (500 mm)
Is set to slightly more than three times the circumference of the roll.

FIG . 6 is a diagram showing an example of the configuration of a control system according to the present invention . In FIG .
0 is a recording device, and 60 is a printing device.

The control device 30 has a CPU and the like, is connected via a power supply (not shown) and the connection cable 14 of the test body 10, and is connected to the test body 10 according to the wiring number of the connection cable 14. The address of each intersection is stored, and the electrodes 112X, 112Y at each intersection of the entire test body 10 are stored.
The change in current during the display is displayed on the display device 40 in real time, and the display data is stored. Further, the control device 30
Controls recording of the expression data on the recording device 50 or printing on the printing device 60.

Next, the operation of measuring the nip pressure according to the above configuration will be described.

First, the connection cable 14 of the test object 10 is connected to the control device 30, and the control device 30, the display device 40, the recording device 50, and the printing device 60 are turned on. Further, the electrophotographic copying machine is switched to a maintenance mode at the time of shipping or maintenance, and the fixing roller 20 is rotated by a maintenance command. At this time, for example, the rotation speed is set to 3.

In this state, the test piece 10 is supplied from its tip to the fixing roller 20 via the transport system of the electrophotographic copying machine. The supplied test body 10 is sandwiched between the heating roll 21 and the pressure roll 22 and simultaneously receives a predetermined pressure in the axial direction of the roll (both sides and the center).

As a result, the resistance values of the pressure-sensitive sensors 113X and 113Y in the portion that receives the pressure change, and the current between the electrodes 112X and 112Y located at these intersections changes in accordance with the change in the resistance value. Is displayed on the display device 40 under the control of the control device 30. That is, the entire roll nip pressure distribution (actually, both sides and the center) in one roll axis direction is simultaneously measured and displayed on the display device 40 in real time.

The measurement and expression of the roll nip pressure distribution are continuously performed over the entire circumference of the roll with the rotation of the roll, and the continuous nip pressure distribution of the entire roll is displayed on the display device 40. Will be revealed. The expression data is recorded on the recording device 50 as necessary, or
Is printed as measurement data including, for example, a measured pressure value.

Based on the expression data and the print data, the nip pressure distribution of the fixing roll 20 is objectively grasped by the operator, and the interval between the heating roll 21 and the pressing roll 22 is adjusted as necessary. Further, the roll nip pressure distribution is measured by the above procedure, and highly accurate roll nip pressure adjustment is realized.

As described above, according to this embodiment,
Electrodes 112X, 1 for outputting an electric signal corresponding to the pressing force
A test body 10 in which pressure-sensitive elements such as 12Y and pressure-sensitive sensors 113X and 113Y are two-dimensionally distributed, is fixed to the fixing roller 2
0 between the two rolls 21 and 22 to simultaneously measure the roll nip pressures on both sides and the center in the axial direction of the rolls, and to display them on the display device 40 in real time, and to determine the size of the test specimen ( (The length in the transport direction) is set to be equal to or greater than the entire circumference of the roll, and this measurement is performed continuously over the entire circumference of the roll, so that a linear pressure distribution can be obtained on the entire circumference of the rotating roll. Can be.
Therefore, it is possible to obtain objective measurement data that is not affected by the skill level of the judge, etc., and realize highly accurate nip pressure adjustment,
Fixing quality can be sufficiently improved.

In this embodiment, the fixing roll of the electrophotographic copying machine has been described as an example. However, the present invention is not limited to the fixing roller. It goes without saying that the method of the present invention can be applied to an apparatus.

In this embodiment, the nip pressure at both sides and the center in the roll axis direction is simultaneously measured. However, the test body 10 is configured so as to be able to measure over the entire roll axis direction. Of course it is good.

Further, in this embodiment, a test body in which the pressure-sensitive elements are arranged in a plane is supplied between the two rolls. However, the pressure-sensitive elements themselves are, for example, all of the pressure rolls of the fixing roller. The same effect as described above can be obtained by arranging the entire surface inside the surface and extracting the output during shipping or maintenance.

[0037]

As described above, according to the first aspect, a linear pressure distribution can be obtained on the entire peripheral surface of the rotating roll, and the objective measurement data is not affected by the skill of the data judge. And a highly accurate nip pressure adjustment can be realized. Further, the distribution state of the nip pressure in the paper transport direction (the direction perpendicular to the axial direction of the roll) can also be measured.

According to claim 2 or claim 3,
The pressure distribution over the entire surface of the roll can be detected linearly and accurately.

[Brief description of the drawings]

FIG. 1 is an external perspective view for explaining an embodiment of a roll nip pressure measuring method according to the present invention.

FIG. 2 is an explanatory view of a conventional roll nip pressure measuring method.

FIG. 3 is a sectional view taken along the line AA in FIG. 1;

FIG. 4 is a diagram showing an arrangement relationship between an electrode and a pressure-sensitive sensor according to the present invention.

FIG. 5 is a diagram showing a relationship between electrodes, through holes, and leads.

FIG. 6 is a configuration diagram of a control system according to the present invention.

[Explanation of symbols]

10: Planar specimen, 11X: first base, 11Y: second base, 111X, 111Y: base, 112X,
112Y ... electrode, 113X, 113Y ... pressure sensor, 1
4, connection cable, 20 fixing roller, 21 heating roller, 22 pressure roller, 30 control device, 40 display device, 50 recording device, 60 printing device.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-183534 (JP, A) JP-A-62-68758 (JP, A) JP-A-60-15533 (JP, A) JP-A-60-183534 169730 (JP, A) JP-A-59-175992 (JP, A) JP-A-3-269331 (JP, A) JP-A 62-124529 (JP, U) JP-A 62-184444 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01L 5/00

Claims (3)

(57) [Claims] 1. A method for measuring a roll nip pressure between two rolls which sandwiches a supplied planar body and feeds the same in a predetermined direction, comprising: a belt-shaped pressure-sensitive element for outputting an electric signal corresponding to a pressing force;
Make sure that the cross section of the rolls overlaps
A plurality of sheet specimens distributed at predetermined intervals in the circumferential direction are supplied between the two rolls, and the roll nip pressure in the axial direction of the rolls is measured based on the output electric signal. Is continuously performed over the entire circumference of the roll. 2. A roll nip pressure measuring test body which is supplied between two rolls and detects a roll nip pressure, wherein a band-shaped pressure-sensitive element for outputting an electric signal corresponding to a pressing force is provided.
Make sure that the cross section of the rolls overlaps
And distribute them at predetermined intervals in the circumferential direction.
And a plurality of strip-shaped electrodes for detecting the electric signals are distributed at predetermined intervals in the axial direction and the circumferential direction of the roll such that the intersections overlap each other, and the roll in the pressure-sensitive element distribution region is provided. A roll nip pressure measurement specimen, wherein the length in the supply direction to the gap is set to be equal to or greater than the entire circumference of the roll. 3. A nip roll for sandwiching and feeding a supplied planar body in a predetermined direction, wherein a band-shaped pressure-sensitive element for outputting an electric signal corresponding to a pressing force is provided.
Make sure that the cross section of the rolls overlaps
And distribute them at predetermined intervals in the circumferential direction.
In addition, a plurality of strip-shaped electrodes for detecting the electric signals are distributed at predetermined intervals in the axial direction and the circumferential direction of the roll so that the intersections overlap each other, and the electrodes and the pressure-sensitive elements are rolled respectively. A nip roll, wherein the nip roll is arranged over the entire circumference of the inside of the surface.